1. Field of the Invention
The present invention relates to an electrodes device for high frequency themotherapy apparatus, which is inserted into a cavity of a living body (an organism), for instance, such as rectum to effect medical treatment against cancer cells at moderately warm temperature.
2. Description of the Prior Art
An electrode device used for high frequency thermotherapy apparatus is generally called applicator. This applicator is made up of an electrode section for applying a high frequency electric field and a cooling section for cooling the skin for protection from burn. A high frequency thermotherapy apparatus is provided with a pair of applicators. In the thermotherapy, one applicator is inserted into a cavity of a living body (e.g. into the rectum from the anus), while the other applicator is arranged on the outer surface of the living body so as to sandwich the disease part between the two applicators. A high frequency electric field is generated between the two applicators to warm or heat the disease part (e.g. cancer cells) for thermotherapy. To cool or protect the inner and outer surface of a living body in contact with these applicators from heat, a cooling device is required for the applicator.
For the applicator arranged outside the body, since the shape of the applicator can be increased easily, it is possible to provide a sufficiently wide cooling space and surface. For the applicator to be inserted into a very narrow cavity of a living body (patient), however, it is impossible to increase the diameter of the applicator (a cavity-inserted cylindrical body). Therefore, the space within the inserted cylindrical body is extremely narrow. In other words, the space where an electrode is arranged or a cooling liquid is passed is every small in volume. In addition, in the prior-art cavity-inserted cylindrical body, since a cooling liquid charging port and a cooling liquid discharge port are only arranged, there exists a problem in that cooling liquid will not flow or circulate and therefore the cooling efficiency is low. When the cavity is not sufficiently cooled, there exists a danger that the mucous membrane is burnt.